What minimum Sn_RXBUF_SIZE and Sn_TXBUF_SIZE should I select for the UDP socket used for Wake Up on LAN?
The magic packet is a broadcast frame containing anywhere within its payload 6 bytes of all 255 (FF FF FF FF FF FF in hexadecimal), followed by sixteen repetitions of the target computer’s 48-bit MAC address, for a total of 102 bytes but the size of the buffer of the W5500 can be set in steps of 1K then the minimum size for this use remains 1K.
Sn_RXBUF_SIZE = 1
Sn_TXBUF_SIZE = 1
As usual in receiving the first 8 bytes of the buffer are:
4 the ip address of the sender
2 port of the sender
2 the number of received bytes number to process